It is now more common to find plantings on the tops of buildings. Structures located on roofs of buildings which support such plantings have become known as green roofs. The green roof eliminates a typically flat, somewhat unattractive surface area and substitutes a garden of plantings for an empty roof. A green roof promotes oxygenation and the elimination of CO2 emission. A green roof can provide food, if the plantings comprise vegetables (urban farming), or beauty, if the plantings comprise flowering plants. A problem with such structures as green roofs has become the fact that many roofs do not have the weight-bearing capacity to support the plantings, the structures in which the plantings are planted and an irrigation system to supplement, at times, a lack of rainfall. On the other hand, without such a green roof, storm water run-off is promoted. With storm-water run-off, rain water that collects on an empty roof is typically fed via gutters and downspouts or roof drains into a water waste system, rather than used for promoting healthy green vegetation. As the rain water flows from the roofs and onto pavement below, it may pick up hazardous wastes from such construction materials as tar and asphalt and the like or become overly acidic or basic and so become destructive to other plant and animal life rather than healthy.
An advantage of a green roof, besides its ability to promote clean oxygenated air, is its ability to help insulate the building on which it sits. For example, a green roof blocks ultra-violet radiation from the sun. Consequently, a green roof may save energy costs. On the other hand, a green roof is difficult to see from the ground. Thus, it is difficult for a building owner or tenant to advertise the fact that their building is “green.” So even though the plantings may be formed into shapes that, for example, advertise the identity of the green promoter, the shapes can only be seen from the sky.
Gold, U.S. Patent Application Pub. No. 2007/0079547, published Apr. 12, 2007, provides an example of a green roof system. Containers for planting medium and plantings may be formed of recycled carpet. These containers may be formed of a base and plural walls. A water permeable root barrier may be positioned to block growth of plant roots into a drainage layer. A roof protective layer protects the roof comprising at least one sheet of water permeable fabric. A drainage mat may have a plurality of water capturing cups with water flow facilitated through gaps between the cups. Other forms of green roof are known as well.
While green roofs promote the environment, there remains a need for extending the concepts of green plantings to vertical structures such as walls of buildings. The planting of green walls and the design of associated structures originated outside the United States and has extended to the United States from abroad. Traditionally, climbing plants may be planted at the foot of a wall. However, such a planting as ivy can be very difficult to remove once planted and may do some damage to the wall surface. Alternatively, support structures such as arbors may be used for flowering plants such as roses and the like. However, these structures are limited by their weight bearing ability to support large plants and may tend to deteriorate over time.
Fukuzumi, U.S. Pat. No. 5,579,603, issued Dec. 3, 1996, discloses a plant growing method for greening wall surfaces whereby a plurality of stacked flexible bags are formed. The flexible bags include a plurality of compartments with openings communicating with the exterior for receiving plantings and plant soil medium. Soil is loaded through openings into bag compartments with the bags laid horizontally while the plantings are allowed to grow. The multi-compartment bag is then suspended along a vertical wall to be made “green.” Water can be supplied into the compartments of the bag to promote the growth of the plantings. A problem with such a wall hanging bag is that the wall must support the weight of the bag, the soil and the plantings. Moreover, the bag may tear over time and the green wall deteriorate, for example, from the growth of plant root structure or the weather. Water running down the wall from rain may be used to moisten the backs of the bags and the plants contained therein. However, the plant root structure thus is encouraged to obtain water from the vicinity of the wall and grow through the bag fabric. The rain and root structure may help the bag fabric to deteriorate. Irrigation piping may be used to intentionally moisten the walls and bag system and drip down to the bags during a lack of rain.
U.S. Pat. No. 4,268,994, to Urai, issued May 26, 1981, describes a three-dimensional planter. The planter may incorporate liquid retention boards attached to the back wall of the planter. These may extend slantingly upward and accumulate water to prevent rapid transmission of water through planting growth material.
Peleszezak of France, U.S. Patent Application Pub. No. 2007/0199241, published Aug. 30, 2007, describes a structure for a vegetated wall of boxes. Buried within the thickness of the boxes in a planting substrate are a network of water pipes and drains. A vertical water pipe is connected with horizontal water pipes at a number of levels to irrigate the boxes. A photovoltaic panel and battery may supply electrical energy to run an irrigation pump and lighting.
Binschedler et al. of France, U.S. Patent Application Pub. No. 2008/0295402, published Dec. 4, 2008, disclose a modular greening device for facades, walls and the like comprising a support structure of at least two parallel vertical rails for receiving individual modules stacked above one another by means of dowels or pins received into respective sockets of the vertical rails. An individual modular greening device is equipped with ribs having perforations at a rear wall. The top and bottom walls of a module are likewise equipped with perforations at the bottom of lateral walls forming a V shape. Thus water collected in a V of a top module is conveyed through the perforations at the bottom of the V to the next structure below. There appear to be gaps between the bottom wall of an upper module and an upper wall of a bottom module per FIG. 4A. Such a structure may encourage splashing and loss of water rather than the water being efficiently provided by gravity feed to vegetation planted in the modules. Moreover, special locking sections are required to maintain the modules in place and, potentially, prevent theft of the modules. A disclosed irrigation system comprises a gutter and a vertical and horizontal irrigation pipe system that is installed separately from the modules.
Garner et al., U.S. Patent Application Pub. No. 2009/0223126, published Sep. 10, 2009, discloses a vertical plant supporting system comprising a matrix of tubes. Growth media is added to a closed cavity defined by each tube in the matrix of tubes. A water supply is positioned along an upper surface of the matrix of tubes and connected to a supply of water that may contain additional plant nutrients.
Recently, a number of metropolitan cities have endorsed the Leadership in Energy and Environmental Design or LEED® standards for new construction of the U.S. Green Building Council. Examples include San Jose, Calif. on the west coast and Baltimore, Md. on the east coast. These standards encourage, as their name suggests, smart energy conservation and environmental design. Consequently, there is an opportunity for further research and development in the field of green structure design.
Each of the above-identified patents and patent applications should be deemed to be incorporated by reference herein as to their entire contents.